基于烃类组成的催化裂解反应规律.

Objective The reaction rules of different hydrocarbon in deep catalytic cracking（DCC） process was studied to improve hydrocarbon utilization rate and selectivity of target products, and explore the potential of “oil to chemicals”. Methods Based on the hydrocarbon compositions of raw oil and products in DCC, the apparent conversion rate of different hydrocarbons from raw oil to products were analyzed in detail, and the conversion and formation pathways of different hydrocarbons were analyzed and discussed. Results During the catalytic cracking reaction, the apparent conversion rates of paraffin hydrocarbons, cycle-hydrocarbons and aromatics were 93.06%, 97.05% and 58.53%, respectively. In the aromatics, the apparent conversion rates of single ring, double ring, third ring, four ring and five rings and above were 61.49%, 11.34%, 65.17%, 29.27% and 96.35%, respectively. The molar ratio of catalytic cracking products to raw oil was 7.68, and the molar ratio of product aromatics to raw oil aromatics was 2.99. Hydrocarbons with mass fraction of 27.50% in the liquid product could be further converted into the target product, and the proportion of monocyclic aromatic hydrocarbons in the product generated by aromatization reaction from the non-aromatics in the feed oil was 96.16%. Conclusions The catalytic cracking conversions of alkanes and cycloalkanes were relatively complete, while the apparent conversion rate of aromatics was relatively low, and the apparent conversions of aromatics with different ring numbers were quite different, showing the characteristics of high apparent conversion rate of aromatic hydrocarbons with odd ring numbers and low apparent conversion rate of aromatic hydrocarbons with even ring numbers. The catalytic cracking reaction and aromatization reaction were the most important reactions of the DCC process. The apparent lightening order of different hydrocarbons was alkanes ＞ monocyclic aromatic hydrocarbons ＞ cycloalkanes ＞ bicyclic aromatic hydrocarbons ＞ tricyclic and above aromatic hydrocarbons. The monocyclic aromatic hydrocarbons in the products mainly came from the aromatization reaction of non-aromatic hydrocarbons in the raw oil. Hydrocarbons that can be converted into target products in liquid products could be further reduced. [ABSTRACT FROM AUTHOR]